Scientific research on the health risks of tattoos has identified a possible long-term health risk: carcinogens in tattoo inks.
Cancer-producing particles are being injected directly into the skin, the Australian paper Financial Review reports, though they don’t seem to produce skin cancers. Experts say this is likely because the ink particles are stable when injected, which they must be for the tattoo to be permanent. But when people want to have tattoos removed, laser removal shatters the pigments, making them unstable and more likely to enter the bloodstream. If particles settle in an area, the harm could build slowly and reveal itself decades later, perhaps in the form of cancer.
When the destabilizing effect was demonstrated, skin clinics and regulatory authorities in some countries questioned the safety of laser removal and there was a downturn in use. “Laser removal of tattoos almost stopped in Germany because of this risk,” says Jørgen Serup, professor of dermatology at Bispebjerg University Hospital in Copenhagen. Professor Serup is a leading researcher into the chemistry of tattoo inks and the body’s reaction to them, according to Financial Review.
Last year, Serup contributed to a report for the Danish government entitled Chemical Substances in Tattoo Ink, which analyzed 65 inks. This year, he co-published a study on black ink, the most commonly used color. The study showed 10 out of 11 black inks—the most common color—contained concentrations of the known carcinogen, polycyclic aromatic hydrocarbon, at levels that exceed European safety recommendations. This carcinogen is also found in soot, tar, and cigarette smoke.
Serup worries about the accumulation of particles in the lymph nodes. Over time, he explains, ink nanoparticles could have an effect similar to the effect of the metals shed by metal-on-metal hip replacement joints. As the hip components move against each other, they can release ions, such as cobalt and chromium, into the bloodstream. The accumulated ions have been associated with effects on the heart, skin, endocrine and nervous system, Financial Review reports. “It took years to convince the medical community that there may be a problem with these joints, so I would not exclude tattoos having a hidden impact on a cancer in any organ system,” says Serup.
Next month, the European Congress on Tattoo and Pigment Research will host the fires-ever medical congress on tattooing to explore the latest science and social science research on tattooing.